Database Administrators Stack Exchange is a question and answer site for database professionals who wish to improve their database skills and learn from others in the community. Join them; it only takes a minute:

Unexpected error: A duplicate object name has been found.
This may occur if the SQL Server that you are registering is case sensitive but the case sensitive option is not set.
RedGate.SQLCompare.Engine.SqlCompareException
at #mWo.#KYo.#0cp(DBPopulationOptions #YBCc)
at #mWo.#HPud.#crc(ConnectionProperties #x1lc, #en #LfCc)
at RedGate.SQLCompare.Engine.Database.#crc(ConnectionProperties #Ap8b, #en #5
OPb)
at #namb.#n9G.#W8G(DataSource #ovUb, #en #5OPb, Boolean #q9rc)
at #i9G.#n9G.#W8G(DataSource #ovUb, #en #5OPb, Boolean #q9rc)
at #i9G.#n9G.#1tD(String #p9rc, DataSource #ovUb, #en #5OPb, Boolean #q9rc)
at RedGate.SQLCompare.CommandLine.CommandProcessor.#lMPb()
at RedGate.SQLCompare.CommandLine.CommandProcessor.#kcmb()
at RedGate.SQLToolsCommandLine.CommandProcessor.#OUb()
at #i9G.#OsPb.#6sc(String[] #ead)
Caused by:
Index was out of range. Must be non-negative and less than the size of the colle
ction.
Parameter name: index
System.ArgumentOutOfRangeException
at System.Collections.BitArray.Set(Int32 index, Boolean value)
at #8rg.#5sg.set_Item(DatabaseLevelPermissionAction #pYrc, PermissionType #iT
c)
at #mWo.#KYo.#MCCc()
at #mWo.#KYo.#ICCc()
at #mWo.#KYo.#0cp(DBPopulationOptions #YBCc)

This question appears to be off-topic. The users who voted to close gave this specific reason:

"Too localized - this could be because your code has a typo, basic error, or is not relevant to most of our audience. Consider revising your question so that it appeals to a broader audience. As it stands, the question is unlikely to help other users (regarding typo questions, see this meta question for background)." – Mikael Eriksson, McNets, Mike Walsh, Mr.Brownstone

But that's not what you showed in the question - your file path is pointing at the SQL Compare 10 directory. Make sure you're pointing it at your SQL Compare 12.4 installation.
– Andrew TimsonJul 13 '17 at 4:22